Electrically actuated security system



May 25, 1970 R. 01. 3,514,611

ELECTRICALLY ACTUATED SECURITY SYSTEM Filed Jan. 26, 1968 was H2ATTORNEYS.

United States Patent US. Cl. 250-208 3 Claims ABSTRACT OF THE DISCLOSURETwo sets of photocells, one set in series with each other and the otherset in parallel with each other, individually control circuit elementssuch that a coded card masking all of the parallel photocells whileunmasking all of the series photocells operates to energize thecircuitry to a mechanism-unlocking condition.

BACKGROUND OF THE INVENTION Various mechanisms are contemporarily in usein which some service is rendered in response to coin deposit, as forexample in coin operated laundry and drying machines. Such machines areprovided with a coin vault which collects and stores the moniesdeposited incidental to the coin operation of the mechanism. These coinvaults ordinarily are provided with a key controlled lock mechanism sothat authorized personnel may periodically open the vault and remove themonies therefrom. Unfortunately, the keys may be duplicated, become lostor due to other circumstances unauthorized personnel may find access tothe coin vaults. It would therefore be desirable to provide some meansfor making the normal key controlled lock more secure. Unfortunatelychange of the tumbler mechanism and concomitant change in the keyconfiguration is costly and time consuming and it would thus beadvantageous to provide some simple means whereby the lock mechanism forthe coin vault could be made more secure. a

BRIEF SUMMARY OF THE INVENTION The present invention seeks to overcomethe above mentioned difiiculties by the provision of an auxiliarysecurity system of an electrical nature which requires possession of acoded card in addition to the proper key for unlocking the coin valutson coin operated machines and the like.

More particularly, the present invention relates to a security controlsystem which consists of requisite electronic circuitry operatingthrough the medium and control of photocells accurately to read out anassociated coded card so as to release or actuate the mechanism only inresponse to presentation of the proper code to the device.

More specifically, the present invention utilizes two sets ofphotocells, the first set being arranged in parallel to each other andthe second set being arranged in series relationship and adapted to beproperly actuated when all of the parallel photocells are darkened andall of the series photocells are energized thus to control associatedcircuitry to actuate the normally locked mechanism to unlockedcondition.

BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWING FIG. 1 is a circuitdiagram showing the operative components of the system.

DETAILED DESCRIPTION OF THE INVENTION Reference characters and 12indicate a first set of photocells which, as shown, are connected inparallel,

each having an energizing lamp 14 and 16 associated therewith. A secondset of photocells as indicated by the Patented May 26, 1970 referencecharacters 18 and 20 having associated light sources 22 and 24, thesecond set 18 and 20 being disposed in series as illustrated.

Any conventional power source for the circuitry shown may be utilized,the specific configuration illustrated in the drawing incorporating arectifying diode 26 connected across a conventional 110 volt alternatingcurrent supply as indicated by reference characters 28 and 30 throughthe medium of a resistor chain 32, 34 and 36 and through a normally openswitch indicated generally by the reference character 38. The conductor40 connects a relatively positive voltage level to the winding 42 of asolenoid or relay controlling the normally open switch 44, the circuitbeing completed through the collector-emitter path of the semi-conductordevice 46. A smoothing capacitor 48 is provided for preventing relaychatter. The con ductor '50 connects the relatively positive potentialpoint (but negative with respect to the conductor 40) to the biasingresistors 52 and 54, and also connects to the photocells 1-0 and 12 inparallel and to the photocells 18 and 20 in series, substantially asshown.

The semi-conductor device 46 is normally non-conducting until a positivegoing signal appears at its base through the resistor 56 and in ordernormally to retain the semiconductor device 46 in non-conductingcondition, the semi-conductor pair 58 and 60 and the associated inverter62 are provided.

In order better to appreciate the operation of the system, let it beassumed for the moment that no card has been inserted but that theswitch 38 nevertheless is in closed condition thus to energize the powercircuitry so that the aforementioned voltages appear on the conductors40 and 50. Under these conditions, the light sources 14, 16, 22 and 24are energized and since no card is present, all of the photocells 10',12, 18 and 20 are likewise energized. The load resistor 64 of theparallel photocells will therefore produce a positive voltage at thejunction 66 and, likewise, the load resistor 68 of the series photocellswill produce a positive voltage at the junction 70. The positive voltageat the junction 66 biases the base of the semi-conductor device 58through the resistor 72 snfiiciently to render this semiconductor deviceconductive. At the same time, the relatively positive voltage at thejunction 70 is sufiicient to bias the semi-conductor 62 through its baseresistor 74 to make this device conductive. Current will flow thereforethrough the resistor 54 producing a relatively negative voltage at thejunction 76 which will turn off the semi-conductor device 60, the baseof which is connected to the junction 76 through the resistor 78. Theconducting condition of the semi-conductor device 58 causes the junction80 to be at a relatively negative potential whereby the base of thesemi-conductor device 46- is insufiiciently biased to conduct and theswitch 44 remains in its normally open condition.

From the above it will appear that in order to actuate the circuitry toan unlocked condition wherein the switch 44 is closed, the devices 58and 60 must both be non-conducting. Obviously, then, a properly codedcard must allow all the series photocells 18 and 20 to be energizedwhile preventing energization of all of the parallel photocells 10 and12. If any one of the parallel photocells 10, 12 are allowed to conduct,the voltage drop across the resistor 64 is sufiicient to bias thesemi-conductor device 58 to conducting condition. Naturally, if any ofthe series photocells 18, 20 is not energized, the resulting negativepotential at the junction 70 will render the semi-conductor device 60conductive.

The machine includes a slot-like mechanism having a base 82 onto whichthe coded card 84 is adapted to be placed and when positioned homecloses the normally open switch 38 to energize the entire circuitryinclusive of the light sources 14, 16, 22 and 24 although the electricconnections thereto have been omitted ror the sake of clarity. The base82 is provided with a transversely enlarged opening 84 and the lightsources and photocells are disposed on relatively opposite sides of thebase in alignment with this opening so that the region 86 of the cardforms the encoding portion thereof. The requisite portions of the card,if properly encoded, serve to mask the light sources associated with theparallel photocells and 12 and to allow energization of the seriesphotocells 18 and 20 so that, under these conditions, the photocells 10and 12 are non-conducting so that the junction 66 goes negativecorrespondingly to render the semi-conductor device 58 non-conducting.Simultaneously, the photocells 18 and 20 are conducting and the junction70' is at a relatively positive potential rendering the semiconductordevice 62 conductive and thereby maintaining the junction 76sufficiently negative as to prevent conduction of the semiconductordevice 60. Both semi-conductor devices 58 and 60 are thus non-conductingand the junction 80 goes relatively positive thereby to render thesemic-onductor device 46 conductive, energizing the winding 42 to closethe normally open switch 44 and complete the circuit through the winding88 of the actuating device. The actuating device may include a suitablemember for unlocking the coin vault.

Obviously, many modifications and variation of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. In an electrically actuated security system of the type including anelectrically-actuated locking mechanism normally disposed in lockedcondition,

a first set of photocells disposed in series relation to each other,

a second set of photocells disposed in parallel relation to each other,

and circuit means responsive to a predetermined condition of said firstand second sets of photocells for actuating said locking mechanism tounlocked condition, said circuit means including a first semi-conductordevice biased to non-conductive condition in response to deenergizationof all of said first set of photocells, a second semi-conductor devicebiased to conductive condition in response to energization of all ofsaid second set of photocells, a third semiconductor device biased tonon-conductive condition in response to conduction of said secondsemi-conductor device, and a fourth semi-conductor device forcontrolling said locking mechanism, said fourth semi-conductor devicebeing biased to conducting condition to unlock said mechanism only inresponse to non-conductive condition of both said first and said thirdsemi-conductor devices.

2. In the system as defined in claim 1 including a card coded as tolight transparency, a receiver for said card, said first and second setsof photocells being located on one-side of said receiver and there beinglight source means on the other side of said receiver.

3. In the system as defined in claim 2 including a power control switchfor said circuit means, said photocells and said light source means,said switch being located in said receiver for actuation by said card inresponse to predetermined positioning of said card in said receiver.

References Cited UNITED STATES PATENTS 2,953,689 9/1960 Becker 250 2093,029,345 4/ 1962 Douglas 250--210 X 3,235,860 2/ 1966 Vassil 250-20 9 X3,383,513 5/1968 Douglas 250-208 WALTER STOLWEIN, Primary Examiner US.Cl. X.R.

